By Troy Dreier
Netflix has reached the end of a four-year project to add intelligence to its video encoding and reduce file sizes by around 20 percent. According to Variety, Netflix engineers realized in 2011 that the adaptive encoding presets it used were wasteful, as they encoded simple animated programs and big-budget action movies in the same way. That meant that watching a cartoon in HD carried the same bandwidth demands as a Hollywood blockbuster.
At first Netflix thought the solution would be to create genre-specific presets, encoding action movies with one standard and cartoons with another. But it quickly discovered that not all movies within a genre have the same demands, and even TV shows can vary by episode. That’s when Netflix decided to apply presets on a title-by-title basic. The company partnered with researchers at the University of Southern California, the University of Nantes, and the University of Texas at Austin to create automated quality-control solutions. Netflix offered a detailed look at how it achieves its encoding savings in a blog post. The lower-bitrate files will help consumers avoid data cap limits and will be an assets as Netflix expands into countries with lower bandwidth averages.
Netflix has rigorously tested newly encoded files to ensure that viewers get an identical image. The company should complete re-encoding its vast video library by the end of Q1 2016. After that, it may dive into an even larger encoding project: re-encoding movies and shows on a scene-by-scene basis, since even within a title some scenes are more visually demanding than others.